A Florida high school student has been charged as an adult after he allegedly appeared in a video with a gun outside his school, threatening to shoot the principal.

Anthony L. Roberson of Riviera Beach is charged with possession of a gun on school property and was being held Thursday on $115,000 bond.

The Palm Beach Post reports the 17-year-old William T. Dwyer High School student did a live online video March 6 outside the school while holding a gun, saying he brings it daily. He then made what authorities inferred to be a threat against the principal.

The video was reported to the Palm Beach County Sheriff's Office, which found a gun at his home the next day. Roberson told investigators he "was only kidding." He was arrested Tuesday.